From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756005AbaEOUit (ORCPT ); Thu, 15 May 2014 16:38:49 -0400 Received: from mail-pb0-f48.google.com ([209.85.160.48]:65124 "EHLO mail-pb0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755786AbaEOUip (ORCPT ); Thu, 15 May 2014 16:38:45 -0400 From: Guenter Roeck To: linux-watchdog@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Wim Van Sebroeck , Catalin Marinas , Maxime Ripard , Will Deacon , Arnd Bergmann , Heiko Stuebner , Russell King , Jonas Jensen , Randy Dunlap , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Guenter Roeck Subject: [PATCH v3 2/6] watchdog: Document reboot API Date: Thu, 15 May 2014 13:38:20 -0700 Message-Id: <1400186304-1691-3-git-send-email-linux@roeck-us.net> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1400186304-1691-1-git-send-email-linux@roeck-us.net> References: <1400186304-1691-1-git-send-email-linux@roeck-us.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Document the new reboot API functionality. Signed-off-by: Guenter Roeck --- v3: Added documentation patch Documentation/watchdog/watchdog-kernel-api.txt | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt index a0438f3..39f8e00 100644 --- a/Documentation/watchdog/watchdog-kernel-api.txt +++ b/Documentation/watchdog/watchdog-kernel-api.txt @@ -90,6 +90,7 @@ struct watchdog_ops { int (*stop)(struct watchdog_device *); /* optional operations */ int (*ping)(struct watchdog_device *); + void (*reboot)(struct watchdog_device *); unsigned int (*status)(struct watchdog_device *); int (*set_timeout)(struct watchdog_device *, unsigned int); unsigned int (*get_timeleft)(struct watchdog_device *); @@ -148,6 +149,8 @@ they are supported. These optional routines/operations are: info structure). * status: this routine checks the status of the watchdog timer device. The status of the device is reported with watchdog WDIOF_* status flags/bits. +* reboot: if this routine is present, it may be called to reboot the system. + Parameter is the pointer to the watchdog device. * set_timeout: this routine checks and changes the timeout of the watchdog timer device. It returns 0 on success, -EINVAL for "parameter out of range" and -EIO for "could not write value to the watchdog". On success this @@ -224,3 +227,11 @@ the device tree (if the module timeout parameter is invalid). Best practice is to set the default timeout value as timeout value in the watchdog_device and then use this function to set the user "preferred" timeout value. This routine returns zero on success and a negative errno code for failure. + +The watchdog_do_reboot function can be used to reboot the system. This is +intended to be used in systems which do not have an explicit reboot capability, +but implement reboot by programming the watchdog to expire immediately. If +the function is called, and a watchdog driver with reboot functionality was +previously registered, the reboot function of that driver will be called. +Architecture code should call watchdog_do_reboot from its machine_reboot +function after other means to reboot the system failed. -- 1.9.1